The present invention concerns an attachment for washing a surface or a carpet, for being attached to the intake wand of a suction cleaner and for also defining the intake nozzle of the suction cleaner. In particular, the washing attachment includes means for storing an appropriate washing liquid, for dispensing that liquid to the surface to be cleaned in the vicinity of the pickup nozzle and for picking up the liquid and any dirt through the intake nozzle.
Some suction cleaners or vacuum cleaners are adapted for picking up wet materials and liquid. Those typically include a liquid and dirt collection tank, an intake suction hose for suctioning liquid from a surface or carpet and for transmitting it to the collection tank, and a suction motor communicating into the suction hose for suctioning material into and through the intake hose into the tank.
Because such a suction cleaner has the capability of collecting liquid from a surface, a natural development for such a suction cleaner was to deliver cleaning liquid to the surface to be cleaned and to thereafter suction the cleaning liquid from the surface after the liquid washed the surface or dissolved or lifted off some of the dirt. A floor or carpet can be more easily cleaned when water or detergent is delivered to it, is spread in an area to be cleaned and is then suctioned off the surface. The suctioning aids in drying the surface and taking away the dirt.
Some suction cleaners were designed as self-contained liquid dispensing and collecting suction cleaners. Other liquid dispensers and collectors have been developed as attachments to the intake hose or wand of a standard wet/dry pickup suction cleaner. The invention concerns an attachment. The liquid may be supplied to the attachment from an external source through a hose or tube or it may be carried on the cleaning attachment in a liquid dispensing tank. Means are needed for dispensing the liquid to the surface to be cleaned when the liquid is needed.
In some known suction cleaner attachments, liquid dispensed is controlled by a manually-operable trigger which opens the appropriate dispensing nozzles or other means for delivering liquid from the liquid supply. In addition, when liquid is fed from these suction cleaner attachments, sometimes it is pumped out periodically or sometimes continuously, which in any event requires a complicated pump mechanism. Further, this often requires manual activation of an automatic pump or manual operation of a manual pump by the operator of the suction cleaner, which not only requires a more complicated attachment, which is more expensive to fabricate, but also requires more operative steps and greater difficulty for the operator.
In other known attachments, once the attachment is placed on the suction cleaner and the suction cleaner is operated, the liquid drips continuously through a metering outlet nozzle of the liquid supply container no matter whether the suction cleaner is suctioning a surface. In this case, there is little useful control over the dispensing of the liquid, that is, until the attachment is removed from the suction cleaner.
Further, it is useful to dispense the liquid over virtually the entire width of the suction inlet to the intake nozzle, so that the value of dispensing the washing liquid is realized over the full width of the nozzle and is not concentrated toward the center or wherever the nozzle for spraying or dispensing is located.
Prior art does not disclose a valve for dispensing wash liquid from the tank, which valve is activated by moving the suction inlet opening to the surface to be suctioned for partially occluding that opening nor any means for activating that valve when the inlet opening is brought to the surface.
For example, U.S. Pat. No. 2,585,186 discloses a vacuum cleaning device with a shutter that moves in response to wheels contacting the floor. But, this is not concerned with dispensing of liquid from a tank.
Further, suction operated liquid dispensing valves for dispensing liquid upon suction being applied to a work surface are known in the art. See, for example, British Pat. No. 1,123,052 and U.S. Pat. Nos. 3,616,482 and 4,723,337. The latter patent discloses floats. But the floats are not part of a suction responsive liquid dispensing valve.